From the ACLU, this is at Liberty.

I'm Emerson Sykes, a staff attorney here at the ACLU and your host.

A year ago this week, the Supreme Court handed down probably the most important privacy

ruling of the digital age in Carpenter v. the United States.

In that case, the police were investigating a string of burglaries and got months of geolocation

data for a suspect to tie him to the crimes. The court ruled that the Constitution protects this information

and that the police need to get a warrant from a judge before accessing that information from a

cell phone company. That decision has all kinds of implications for the digital data we leave

behind us as we go about our lives. So what is the legacy of Carpenter one year on? Our guest

today is well placed to help us understand how we can hope to protect our privacy, despite the array of digital technologies aimed at tracking our every move and decision. We have in the studio Nathan Fried Wessler, the ACLU attorney who argued and won the case. Nate, thanks very much for joining us. Welcome to the podcast.

Thanks, Emerson. Happy to be here.

Nate, can we just start by you giving us a bit of background about what exactly the Supreme

Court decided in the Carpenter case? So the Carpenter case, it was really about two things.

It was about our location privacy in the digital age. It was a case where police had, in the course of investigating a series of robberies in the Detroit area, they'd gotten a court order, not a search warrant, a court order on a much easier legal standard to get, and sent it to a pair of cell phone companies to get a bunch of suspects historical cell phone location data. This is information that our cell phone companies collect about us

anytime we use our phone to make a receive a call, send a text message. We even just make a data

connection while the phone is passively sitting in our pocket, checking email. And there's this

rich trove of location data sitting at the phone companies that can chart our movements really

at a minute-to-minute level in some cases. So police had gotten this in order to investigate whether some suspects were at the scene of a series of robberies at the times of those robberies. And it turned out, Mr. Carpenter was one of the suspects. And when an FBI agent looked at the data, it placed him near the scene of some of these robberies. and that became really critical evidence at trial.

What the government argued in this case is that it didn't matter how sensitive this information was, didn't matter that it came from Mr. Carpenter's use of his cell phone.

The fact that they got it from the cell phone company rather than out of Mr. Carpenter's pocket

itself just eliminated any argument under the Fourth Amendment to the U.S.

Constitution. That's called the third-party doctrine, that argument. It comes out of a pair of cases from the

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